INSYS GPRS mini
Electrical Description
4.4
RS232 Serial Port
The modem supports a standard RS232 serial interface via its 9 pin Sub-D
connector, shown below. In line with serial communication terminology the
INSYS GPRS mini should be considered as the
data circuit-terminating
equipment
(DCE) and the external application or computer as the
data termi-
nating equipment
(DTE). The maximum baud rate to communicate with the
INSYS GPRS mini is 230400 kbit/s.
The electrical characteristics of the serial port signals are shown below:
PIN
Signal
Direction
Voltage levels
Description
1
DCD
Output
> + 4V
<- 4 V
Data carrier detect
2
RD
Output
> + 4V
<- 4 V
Received data
3
TD
Input
> + 2,4V
< 0.8 V
Transmitted data
4
DTR
Input
> + 4V
< 0.8 V
Data terminal ready
5
GND
-
0 V
Ground connection
6
DSR
Output
> + 4V
< - 4 V
Data set ready
7
RTS
Input
> + 2,4V
< 0.8 V
Request to send
8
CTS
Output
> + 4V
< - 4 V
Clear to send
9
RI
Output
> + 4V
< - 4 V
Ring indicator
4.5
Serial Data
The modem supports the standard data character format of
Programmable baud rate (300bps to 230,400bps).
Auto-configuration mode with auto-baud (1,200bps to 230,400bps).
Multiplex ability according to GSM 07.10 Multiplexer Protocol.
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